粒径对水合氧化镧除氟效果的影响  

Influence of Particle Size on Fluoride Removal by La_2O_3·nH_2O

作　　者：王莉莉[1] 杨宏伟[1] 祝万鹏[1] 李振瑜[1] 刘文君[1] 

机构地区：[1]清华大学环境科学与工程系,北京100084

出　　处：《环境科学研究》2009年第1期103-107,共5页Research of Environmental Sciences

基　　金：国家"十一五"科技支撑计划项目(2006BAD01B02)

摘　　要：针对La2O3.nH2O的高效除氟作用,确定了La2O3.nH2O除氟的最佳pH,在此基础上研究了La2O3.nH2O的粒径对其除氟容量以及除氟动力学的影响,并与活性氧化铝除氟效果进行了对比.结果表明:La2O3.nH2O除氟的最佳pH为5.5～6.5;La2O3.nH2O对氟的吸附基本符合Langmuir单分子层吸附原理;随着粒径的减小,其最大吸附容量及吸附速率均有明显的提高.试验中粒径为0.038～0.050mm的La2O3.nH2O与粒径为>0.500～0.710mm的La2O3.nH2O相比,前者的最大吸附容量是后者的3.32倍;当平衡ρ(氟)为1mg/L时,前者计算所得的吸附容量是后者的10.13倍.与活性氧化铝相比,当平衡ρ(氟)为1mg/L时,相同粒径的La2O3.nH2O的吸附容量是活性氧化铝的2.55～13.88倍.The best pH range for fluorine removal using La2O3·nH2O, and the influence of particle size on its defluorination capacity and dynamics were studied in this paper. On this basis, the defluorination capacity of La2O3·nH2O was compared with activated alumina. The experimental results showed that： the best pH range of fluorine removal using La2O3·nH2O was 5.5-6.5; the adsorption of fluoride on La2O3·nH2O accorded with the Langmuir single molecular layer adsorption principle; and, the maximum adsorption capacity and adsorption rate were significantly improved with the particle size decreasing. In these experiments, the maximum adsorption capacity of La2O3·nH2O with size 0.038-0.050 mm was 3.32 times as much as that with size 〉 0.500-0.710 mm, and when the balance fluoride concentration was 1 mg/L, the calculated adsorption capacity of the former size was 10.13 times as much as that of the latter size. Compared with activated alumina, when the balance fluoride concentration was 1 mg/L, the capacity of La2O3·nH2O was 2.55-13.88 times as much as that of activated alumina with the same particle size.

关 键 词：水合氧化镧 活性氧化铝 除氟 粒径 

分 类 号：X703[环境科学与工程—环境工程]